1. Field of the Invention
The present general inventive concept relates to a photo-curable resin composition, a method of patterning the photo-curable resin composition layer, and an ink jet head and method of fabricating the same and, more particularly, to a photo-curable resin composition including a photo-catalyst as a photo-initiator, a method of patterning a photo-curable resin layer made of the photo-curable resin composition, an ink jet head having the photo-curable resin layer, and a method of fabricating the same.
2. Description of the Related Art
An ink jet recording device functions to print an image by ejecting fine droplets of ink to a desired position of a recording medium. Such an ink jet recording device has been widely used since its price is low and numerous kinds of colors can be printed at a high resolution. The ink jet recording device basically includes an ink jet head for actually ejecting the ink and an ink container in fluid communication with the ink jet head. The ink stored in the ink container is supplied into the ink jet head through an ink channel, and the ink jet head ejects the ink supplied from the ink container to the recording medium to thereby complete a printing operation. An ink ejection type of the ink jet recording device is classified into an electro-thermal transducer type (hereinafter, referred to as “bubble-jet type”) ejecting the ink by generating bubbles in the ink using a heat source and an electro-mechanical transducer type ejecting the ink by controlling a change of an ink volume using deformation of a piezo-electric body used therein.
FIG. 1 is a perspective view illustrating a conventional bubble-jet ink jet head disclosed in U.S. Pat. No. 4,882,595.
Referring to FIG. 1, the bubble-jet ink jet print head includes a substrate 10, a chamber plate 14 disposed on the substrate 10 to form an ink chamber 12 for receiving the ink, a heat-generating resistor 16 disposed in the ink chamber 12, and a nozzle plate 20 having a nozzle 18 for ejecting the ink. The ink is filled in the ink chamber 12 through a restrictor 22, and also filled in the nozzle 18 in fluid communication with the ink chamber 12 using a capillary phenomenon. When the heat-generating resistor 16 is energized, the heat-generating resistor 16 generates heat to form bubbles in the ink filled in the ink chamber 12. As the bubbles are expanded, the ink filled in the ink chamber 12 is pressurized to eject the ink through the nozzle 18.
In order to make the ink jet printer operate reliably and stably, each component disclosed hereinabove should satisfy predetermined conditions. In particular, the chamber plate 14 and the nozzle plate 20 should satisfy the following conditions as a structure for forming a fluid channel (hereinafter, referred to as “fluid channel structure”), in which the ink is moved and temporarily stored. That is, the chamber plate 14 and the nozzle plate 20 should have a high mechanical strength for maintaining a structural shape, the substrate 10 and other layers should have good adhesive properties, and the ink should have corrosion resistance properties. In addition, the chamber plate 14 and the nozzle plate 20 should have a fine structure so as to perform patterning, and should also have good photosensitivity and resolution for patterning the chamber plate 14 and the nozzle plate 20.
Research on a photo-curable resin composition as a material of a fluid channel structure satisfying the above-described conditions has been performed. For example, U.S. Pat. No. 4,623,676 discloses a photo-curable composition containing a polymerizable acrylic compound, a polymerizable epoxy functional silane, and a free radical aromatic complex salt photo-initiator. Further, U.S. Pat. No. 5,907,333 discloses a photo-curable resin composition containing a di-functional epoxy compound, a multi-functional epoxy compound, an aromatic complex salt photo-initiator and a non-photo reactive solvent.
Furthermore, U.S. Pat. No. 4,090,936, U.S. Pat. No. 5,478,606, etc., discloses various photo-curable resin compositions. However, none of the disclosed photo-curable resign compositions entirely satisfy the conditions described above. Therefore, the research on the fluid channel structure needs to be continuously performed to satisfy at least the above conditions.